"Lava has been forced not only into vertical cracks, but also between the layers of stratified rock, where it has hardened and forms more or less horizontal sills. In some instances the quantity of liquid rock forced into one locality is sufficient to raise the overlying strata into a dome which appears upon the surface of a mountain. Such accumulation of igenous material in the midst of sedimentary rocks are called laccolites." -Dryer, 1901

Laccolite

"Lava has been forced not only into vertical cracks, but also between the layers of stratified rock,…

A geological dip of strata.

Strata Dip

A geological dip of strata.

Anticlinal strata is a geological fold upwards with the oldest layer at the core.

Anticlinal Strata

Anticlinal strata is a geological fold upwards with the oldest layer at the core.

Synclinal strata is a geological fold downwards.

Synclinal Strata

Synclinal strata is a geological fold downwards.